For decades, scientists couldn’t figure out how orange cats got their pumpkin-colored coats. No one knew what gene, or unit of hereditary material, was responsible. But now, two independent research groups have found a mutation, or change, in a gene that scientists thought wasn’t related to fur color.
This particular gene is on the X chromosome, which carries genetic information. Females have two X chromosomes, so they need the mutation on both to turn orange. Male cats have one X chromosome and one Y, so they only need one mutation. That’s why most orange cats are male. “Everything you need to know about genetics, you can learn from your cat,” says Leslie Lyons, a cat genetics expert at the University of Missouri.